I have many products that make more than $1000 a month. Tip - use the app stores to cut away the pain of having to market to users through vague means. App stores are a godsend if you are a good developer but bad marketer.
Would you care to elaborate on which app stores. I can see how people can make money developing mobile apps, but is it possible to get a decent revenue from say Chrome Webstore.
Why must it be a web app? To me web apps are only useful for a specific sort of software, not for all types of software. People who want everything to be web apps are just mentally inflexible.
The app store for web apps is twitter and facebook.
I don't know where you read that. Here is the question:
"Is it hard to build, market and maintain a web app that makes at least $1000 a month? For a single, skilled web developer."
You might consider that splitting hairs, but I think the question was quite clear, and very precise. Basically, he's interested in capitalizing on an existing skill set and wondering about the business side of things.
Offtopic I know, but this comment is exactly the type where seeing points on comments would be really useful. As it stands, I won't click this link because I have no idea if it's worth it, or worse some kind of scam.